Identification of procyanidins and anthocyanins in blueberries and cranberries (Vaccinium spp.) using high-performance liquid chromatography/mass spectrometry

Blueberries and cranberries were analyzed for procyanidins using normal-phase HPLC/MS. Monomers, identified as (+)-catechin and (-)-epicatechin, and a series of oligomers were detected in blueberries, and MS data confirmed that the oligomers consisted of (epi)catechin units that were exclusively singly linked (B-type). The procyanidin "fingerprints" were similar for Tifblue and Rubel but higher than that for lowbush blueberries. In whole cranberries, (-)-epicatechin was present, along with a complex series of oligomers. Both A-type (contained only one double linkage per oligomer) and B-type oligomers were present. Two commercial cranberry juices exhibited similar procyanidin profiles, except that one contained increased quantities. There were processing effects on the procyanidin content of cranberry extract and juices when compared to those of the unprocessed fruits. Monomer, dimers, and A-type trimers were the primary procyanidins, with only trace levels of the B-type trimers and A-type tetramers and with an absence of the higher oligomers in cranberry extract and juices.     

Oxygen radical absorbing capacity of phenolics in blueberries,cranberries, chokeberries,and lingonberries

The antioxidant activity of phenolics in fruits of blueberry (Vaccinium corymbosum cv. Sierra), cranberry (Vaccinium macrocarpon cv. Ben Lear), wild chokeberry (Aronia melanocarpa), and lingonberry (Vaccinium vitis-idaea cv. Amberland) was determined in this study. The phenolic constituents and contents among the different berries varied considerably. Anthocyanins were found to be the main components in all these berries. Chlorogenic acid in blueberry, quercetin glycosides in cranberry and lingonberry, and caffeic acid and its derivative in chokeberry were also present in relatively high concentrations. Chlorogenic acid, peonidin 3-galactoside, cyanidin 3-galactoside, and cyanidin 3-galactoside were the most important antioxidants in blueberry, cranberry, wild chokeberry, and lingonberry, respectively. The contribution of individual phenolics to the total antioxidant capacity was generally dependent on their structure and content in the berries. Phenolics such as quercetin and cyanidin, with 3',4'-dihydroxy substituents in the B ring and conjugation between the A and B rings, had highly effective radical scavenging structures in blueberries, cranberries, chokeberries, and lingonberries. Phenolic acids such as caffeic acid also showed high antioxidant activity, probably due to its dihydroxylation in the 3,4 positions as hydrogen donors.     

Lingonberry (Vaccinium vitis-idaea) and European cranberry (Vaccinium microcarpon) proanthocyanidins: isolation, identification, and bioactivities

European, small-fruited cranberries (Vaccinium microcarpon) and lingonberries (Vaccinium vitis-idaea) were characterized for their phenolic compounds and tested for antioxidant, antimicrobial, antiadhesive, and antiinflammatory effects. The main phenolic compounds in both lingonberries and cranberries were proanthocyanidins comprising 63-71% of the total phenolic content, but anthocyanins, hydroxycinnamic acids, hydroxybenzoic acids, and flavonols were also found. Proanthocyanidins are polymeric phenolic compounds consisting mainly of catechin, epicatechin, gallocatechin, and epigallocatechin units. In the present study, proanthocyanidins were divided into three groups: dimers and trimers, oligomers (mDP 4-10), and polymers (mDP > 10). Catechin, epicatechin, A-type dimers and trimers were found to be the terminal units of isolated proanthocyanidin fractions. Inhibitions of lipid oxidation in liposomes were over 70% and in emulsions over 85%, and in most cases the oligomeric or polymeric fraction was the most effective. Polymeric proanthocyanidin extracts of lingonberries and cranberries were strongly antimicrobial against Staphylococcus aureus, whereas they had no effect on other bacterial strains such as Salmonella enterica sv. Typhimurium, Lactobacillus rhamnosus and Escherichia coli. Polymeric fraction of cranberries and oligomeric fractions of both lingonberries and cranberries showed an inhibitory effect on hemagglutination of E. coli, which expresses the M hemagglutin. Cranberry phenolic extract inhibited LPS-induced NO production in a dose-dependent manner, but it had no major effect on iNOS of COX-2 expression. At a concentration of 100 μg/mL cranberry phenolic extract inhibited LPS-induced IL-6, IL-1β and TNF-α production. Lingonberry phenolics had no significant effect on IL-1β production but inhibited IL-6 and TNF-α production at a concentration of 100 μg/mL similarly to cranberry phenolic extract. In conclusion the phenolics, notably proanthocyanidins (oligomers and polymers), in both lingonberries and cranberries exert multiple bioactivities that may be exploited in food development.     

Increased salicylate concentrations in urine of human volunteers after consumption of cranberry juice

The aim of this study was to assess whether regular consumption of cranberry juice results in elevations in urinary salicylate concentrations in persons not taking salicylate drugs. Two groups of healthy female subjects (11/group) matched for age, weight, and height consumed 250 mL of either cranberry juice or a placebo solution three times a day (i.e., 750 mL/day) for 2 weeks. At weekly intervals, salicylic acid and salicyluric acid (the major urinary metabolite of salicylic acid) concentrations were determined in urine by HPLC with electrochemical detection. Concentrations of salicylic acid in plasma were also determined. Consumption of cranberry juice was associated with a marked increase (p < 0.001) of salicyluric and salicylic acids in urine within 1 week of the intervention. After 2 weeks, there was also a small but significant (p < 0.05) increase in salicylic acid in plasma. The regular consumption of cranberry juice results in the increased absorption of salicylic acid, an anti-inflammatory compound that may benefit health.     

Separation, characterization and quantification of phenolic compounds in blueberries and red and black currants by HPLC-DAD-ESI-MSn

The phenolic profile of four blueberry varieties (Vaccinium corymbosum L., cv. Toro, Legacy, Duke and Bluecrop) and two varieties (Rosenthal and Rovada) of red currants (Ribes rubrum L.) and black currants (Ribes nigrum L.) cultivated in Macedonia have been analyzed using HPLC coupled to diode-array detection and tandem mass spectrometry with electrospray ionization. A complex profile of anthocyanins, flavonols, flavan-3-ols and hydroxycinnamic acid derivatives has been assayed in acetone-acetic acid (99:1, v/v) extracts. Anthocyanins comprised the highest content of total phenolic compounds in currants (>85%) and lower and variety dependent in blueberries (35-74%). Hydroxycinnamic acid derivatives comprised 23-56% of total phenolics in blueberries and 1-6% in currants. Chlorogenic acid was the major hydroxycinnamic acid in blueberries, only in the Legacy variety, two malonyl-caffeoylquinic acid isomers were major components. Flavonols, mainly quercetin and myricetin glycosides, were a minor group, but glucosides of laricitrin and syringetin were also detected in the blueberry varieties counting for 10-34% of total flavonols. From flavan-3-ols, catechin was detected in most samples; the dimer B2 was specific for blueberries whereas epigallocatechin was detected in currants.     

Phenolic composition of kiwifruit juice

Phenolic compounds in kiwifruit pulp were separated and characterized by reversed-phase HPLC, and the effect of juice processing on the phenolic composition was studied. Fractionation of phenolic compounds was achieved through selective elution from C-18 cartridges prior to preconcentration and subsequent separation by HPLC. Strongly acidic compounds were identified as derivatives of coumaric and caffeic acids, including chlorogenic acid, protocatechuic acid, and a derivative of 3,4-dihydroxybenzoic acid. The weakly acidic fraction contained epicatechin, catechin, and procyanidins (B3, B2, or B4 and oligomers). Flavonols were present as the glycosides of quercetin (glucoside, rhamnoside, and rutinoside) and kaempferol (rhamnoside and rutinoside). Phenolic compounds were present, at levels of <1-7 mg/L, in clarified juice. The concentration of phenolics was highest after high-temperature short-time treatment (HTST) of juice. Hydrolysis of hydroxycinnamic acids occurred after enzyme addition and HTST treatment. The flavonol glycoside composition is the best identifier of kiwifruit juice.     

Phenolic acid profiles in some small berries

The composition of phenolic acids in several small berries grown in Northeastern Poland, namely, low-bush blueberries, black mulberries, European juneberries, black currants, fruits of blue-berried honeysuckle, and blackberries, was determined by gas chromatography (GC) and mass spectrometry (MS). The total content of phenolic acids, identified by GC-MS, ranged from 2845.8 +/- 141.0 (black mulberries) to 5418.2 +/- 228.0 (blue-berried honeysuckle). Twenty phenolic acids were identified in the berries. Of these, hydroxycaffeic, m- and p-coumaric, and 3,4-dimethoxycinnamic acids were the major phenolic acids in blackberries and blueberries, m-coumaric acid was the major phenolic acid in blue-berried honeysuckle and black currant fruits, while salicylic, caffeic, and m- and p-coumaric acids were the predominant phenolic acids in European juneberries. Syringic and veratric acids were detected only in blueberries, while p-hydroxybenzoic and sinapic acids were present only in black currants and o-coumaric acid was present in blueberries and black mulberries. The phenolic acids liberated from esters and glycosidic bonds were the major fractions of phenolic acids in the berries.     

Identification of TLC markers and quantification by HPLC-MS of various constituents in noni fruit powder and commercial noni-derived products

The composition of noni (Morinda citrifolia) products has been investigated. TLC profiles of several commercial juices and capsules were compared. 3-Methyl-1,3-butanediol was identified as a typical marker in noni juices. The presence of sorbic acid (E200) was detected in one juice declared as additive free. Quantitative data have been obtained by HPLC-MS. A method for the quantification of characteristic noni constituents, such as iridoid glucosides, scopoletin, rutin, fatty acid glucosides, and anthraquinones, was developed and validated. The separation was performed on a C18 column with a gradient of acetonitrile in water containing 0.1% formic acid. Detection was carried out with ESI-MS in the negative ion mode. Significant differences were observed between the products. Asperulosidic acid, deacetylasperulosidic acid, and rutin were present in all samples analyzed, but their concentrations differed considerably between the products. Fatty acid glucosides, noniosides B and C, were present in capsules and most juices. Scopoletin was mainly found in juices. The anthraquinone alizarin, which has been reported from roots and leaves, was not detected in the samples investigated.     

Influence of domestic processing and storage on flavonol contents in berries

Effects of domestic processing and storage on the flavonols quercetin, myricetin, and kaempferol in five berries were studied using an optimized RP-HPLC method with UV and diode array detection after an acid hydrolysis of the corresponding glycosides. In fresh berries, the total content of flavonols was highest in lingonberry (169 mg/kg) and black currant (157 mg/kg), intermediate in bilberry (41 mg/kg) and strawberry (17 mg/kg), and lowest in red raspberry (9.5 mg/kg). Cooking strawberries with sugar to make jam resulted in minor losses (quercetin 15%, kaempferol 18%). During cooking of bilberries with water and sugar to make soup, 40% of quercetin was lost. Traditional preservation of crushed lingonberries in their own juice caused a considerable (40%) loss of quercetin. Only 15% of quercetin and 30% of myricetin present in unprocessed berries were retained in juices made by common domestic methods (steam-extracted black currant juice, unpasteurized lingonberry juice). Cold-pressing was superior to steam-extraction in extracting flavonols from black currants. During 9 months of storage at 20 C, quercetin content decreased markedly (40%) in bilberries and lingonberries, but not in black currants or red raspberries. Myricetin and kaempferol were more susceptible than quercetin to losses during storage.     

Stability and enhancement of berry juice color

Attractive color is one of the main sensory characteristics of fruit and berry products. Unfortunately, the color of red juices is unstable and easily susceptible to degradation, leading to a dull and weak juice color. This study was designed to investigate the color stability and copigmentation of four different berry juices enhanced by phenolic acids and commercial color enhancers. Phenolic acid enrichment improved and stabilized the color of the berry juices during storage. The commercial color enhancers immediately produced an intensive color to the juices, which, however, was not very stable. The color enhancement was intensive in strawberry and raspberry juices and effective in lingonberry and cranberry juices. Sinapic acid induced the strongest color in strawberry juice. Ferulic and sinapic acids improved raspberry juice color equally. Rosmarinic acid enhanced the color of lingonberry and cranberry juices the most. The addition of the simple cinnamic acids produced novel peaks to the end of the high-performance liquid chromatography chromatogram, indicating a formation of new compounds. It can be assumed that sinapic and ferulic acids formed new intramolecular copigmentation compounds with berry anthocyanins whereas rosmarinic acid stabilized anthocyanins intermolecularly.     

Characterization of anthocyanins in grape juices by ion trap liquid chromatography-mass spectrometry

A reverse phase HPLC and electrospray interface with ion trap mass spectrometer method was developed for the characterization of anthocyanins in Concord, Rubired, and Salvador grape juices. Rubired and Salvador grapes are hybrids from Vitis vinifera and Vitis rupestris. Concord grape is a grape from the native American cultivar Vitis labrusca. Individual anthocyanins in these three varieties were identified on the basis of UV-vis and MS spectra and further elucidated by MS/MS spectra. Anthocyanins in Salvador and Concord grapes were 3-O-glucosides, 3-O-(6' '-O-p-coumaroyl)glucosides, 3-O-(6' '-O-p-acetyl)glucosides, 3,5-O-diglucosides, and 3-O-(6' '-O-p-coumaroyl)-5-O-diglucosides of delphinidin, cyanidin, petunidin, peonidin, and malvidin. Vitisin B was detected in Salvador grape juice. Anthocyanins in Rubired grape juice were primarily anthocyanin diglucosides: peonidin 3,5-O-diglucoside, malvidin 3,5-O-diglucoside, peonidin 3-O-(6' '-O-p-coumaroyl)-5-O-diglucoside, and malvidin 3-O-(6' '-O-p-coumaroyl)-5-O-diglucoside are the four major anthocyanins. The presence of pelargonidin 3-O-glucoside, not previously reported, has been established for the first time in all three juices.     

Phenolics in Slovenian bilberries ( Vaccinium myrtillus L.) and blueberries ( Vaccinium corymbosum L.)

Phenolics from bilberries ( Vaccinium myrtillus L.) sampled from seven different locations and highbush blueberries ( Vaccinium corymbosum L.) from one location in Slovenia were analyzed. In samples of both species 15 anthocyanins were identified by LC-MS/MS. Their contents were expressed as cyanidin 3-glucoside equivalents (C3GE); bilberries contained 1210.3 ± 111.5 mg C3GE/100 g fw and blueberries 212.4 ± 14.1 mg C3GE/100 g fw. Glycosides of delphinidin and cyanidin were predominant (488.5 vs 363.6 mg C3GE/100 g fw) in the bilberries and glycosides of malvidin (108.0 vs 100.8 mg C3GE/100 g fw) in the blueberries, whereas the contents of peonidin were lowest (74.5 vs 4.8 mg C3GE/100 g fw) in both berries. The contents of flavanols, flavonols, phenolic acids, and stilbenes were determined by LC-MS. For the first time, rutin was identified (bilberries, 0.2 ± 0.0 mg/100 g fw; blueberries, 3.1 ± 0.1 mg/100 g fw). Chlorogenic acid (as 3-caffeoylquinic acid) was the most abundant among the phenolic acids (23.1 ± 1.0 mg/100 g fw in bilberries and 70.0 ± 3.4 mg/100 g fw in blueberries). Statistical analysis shows that the content of 27 individual flavonoids, phenolic acids, and stilbenes can be used to identify the picking region of these Slovenian bilberries.     

Characterization of flavonols in cranberry (Vaccinium macrocarpon) powder

Flavonoids were extracted from cranberry powder with acetone and ethyl acetate and subsequently fractionated with Sephadex LH-20 column chromatography. The fraction eluted with a 60% methanol solution was composed primarily of phenolic constituents with maximum absorbance at 340 nm. A high-performance liquid chromatography procedure was developed, which resolved 22 distinct peaks with UV/vis and mass spectra corresponding to flavonol glycoside conjugates. Six new constituents not previously reported in cranberry or in cranberry products were determined through NMR spectroscopy to be myricetin-3-beta-xylopyranoside, quercetin-3-beta-glucoside, quercetin-3-alpha-arabinopyranoside, 3'-methoxyquercetin-3-alpha-xylopyranoside, quercetin-3-O-(6' '-p-coumaroyl)-beta-galactoside, and quercetin-3-O-(6' '-benzoyl)-beta-galactoside. Quercetin-3-O-(6' '-p-coumaroyl)-beta-galactoside and quercetin-3-O-(6' '-benzoyl)-beta-galactoside represent a new class of cranberry flavonol compounds with three conjugated components consisting of a flavonol, sugar, and carboxylic acid (benzoic or hydroxycinnamic acids). This is also the first report identifying quercetin-3-arabinoside in both furanose and pyranose forms in cranberry. Elucidation of specific flavonol glycosides in cranberry is significant since the specificity of the sugar moiety may play a role in the bioavailability of the flavonol glycosides in vivo.     

Identification of (poly)phenolic compounds in concord grape juice and their metabolites in human plasma and urine after juice consumption

Analysis of Concord grape juice by HPLC with ESI-MS(n), PDA, and fluorescence detection resulted in the identification and quantification of 60 flavonoids and related phenolic compounds, which were present at an overall concentration of 1508 ± 31 μmol/L. A total of 25 anthocyanins were detected, which were mono- and di-O-glucosides, O-acetylglucosides, O-p-coumaroyl-O-diglucosides, and O-p-coumaroylglucosides of delphinidin, cyanidin, petunidin, peonidin, and malvidin. The anthocyanins represented 46% of the total phenolic content of the juice (680 μmol/L). Tartaric esters of hydroxycinnamic acids, namely, trans-caftaric and trans-coutaric acids, and to a lesser extent trans-fertaric acid accounted for 29% of the phenolic content, with a total concentration of 444 μmol/L, of which 85% comprised trans-caftaric acid. Free hydroxycinnamic acids were also quantified but contributed to <1% of the total phenolic content (8.4 μmol/L). The other groups of polyphenolic compounds present in the juice, accounting for 24% of the total, comprised monomeric and oligomeric units of (epi)catechin and (epi)gallocatechin (248 μmol/L), flavonols (76 μmol/L), gallic acid (51 μmol/L), and trans-resveratrol (1.5 μmol/L). The bioavailability of the (poly)phenolic compounds in 350 mL of juice was investigated following acute intake by healthy volunteers. Plasma and urine were collected over 0-24 h and analyzed for parent compounds and metabolites. In total, 41 compounds, principally metabolites, were identified.     

Scavenging capacity of berry crops on superoxide radicals, hydrogen peroxide, hydroxyl radicals, and singlet oxygen

The antioxidant activities against superoxide radicals (O(2)(*)(-)), hydrogen peroxide (H(2)O(2)), hydroxyl radicals (OH(*)), and singlet oxygen ('O(2)) was evaluated in fruit juice from different cultivars of thornless blackberries (Rubus sp.), blueberries (Vaccinium spp.), cranberries (Vaccinium macrocarpon Aiton), raspberries (Rubus idaeus L. and Rubus occidentalis L.), and strawberries (Fragaria x ananassa Duch.). Among the different cultivars, juice of 'Hull Thornless' blackberry, 'Earliglow' strawberry, 'Early Black' cranberry, 'Jewel' raspberry, and 'Elliot' blueberry had the highest antioxidant capacity against superoxide radicals (O(2)(*)(-)), hydrogen peroxide (H(2)O(2)), hydroxyl radicals (OH(*)), and singlet oxygen ('O(2)). In general, blackberries had the highest antioxidant capacity inhibition of O(2)(*)(-), H(2)O(2), and OH(*). Strawberry was second best in the antioxidant capacity assay for these same free radicals. With regard to 'O(2) scavenging activity, strawberry had the highest value, while blackberry was second. Cranberries had the lowest inhibition of H(2)O(2) activity. Meanwhile, blueberries had the lowest antioxidant capacity against OH(*) and 'O(2). There were interesting and marked differences among the different antioxidants in their abilities to scavenge different reactive oxygen species. beta-Carotene had by far the highest scavenging activity against 'O(2) but had absolutely no effect on H(2)O(2). Ascorbic acid was the best at inhibiting H(2)O(2) free radical activity. For OH(*), there was a wide range of scavenging capacities from a high of 15.3% with alpha-tocopherol to a low of 0.88% with ascorbic acid. Glutathione had higher O(2)(*)(-) scavenging capacity compared to the other antioxidants.     

Characterization of major anthocyanins and the color of red-fleshed Budd Blood orange (Citrus sinensis)

High-performance liquid chromatography (HPLC) with photodiode array detection was applied for the characterization of anthocyanins in red-fleshed Budd Blood (Citrus sinensis) orange. More than seven anthocyanin pigments were separated within 30 min by using a binary gradient (0.1% H(3)P0(4) in water and 0.1% H(3)PO(4) in acetonitrile) elution on a Prodigy ODS column. Separations by reversed-phase HPLC and semipreparative HPLC on a Prodigy 10-microm ODS Prep column, and acid and alkali hydrolyses were used for identification of anthocyanins. The primary anthocyanins in Budd Blood orange grown in Florida were cyanidin-3-(6"-malonylglucoside) (44.8%) followed by cyanidin-3-glucoside (33.6%). Two other minor pigments were also acylated with malonic acid. Malonated anthocyanins represented the major proportion (>51%) of anthocyanins in Budd Blood orange. Total anthocyanin contents and juice color parameters (CIE L,a,b) were compared with six other Florida-grown blood oranges.     

Uptake and transformation of pesticide metabolites by duckweed (Lemna gibba)

Uptake and transformation of 14C-labeled metabolites from several pesticides, 3-methyl-4-nitrophenol (1), 3,5-dichloroaniline (2), 3-phenoxybenzoic acid (3), (R,S)-2-(4-chlorophenyl)-3-methylbutanoic acid (4), and (1RS)-trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylic acid (5), were examined by using duckweed (Lemna gibba) in Hoagland's medium. More uptake into duckweed from the exposure water at pH 7.0 was observed for non-ionized 1 and 2 than for 3-5 in an ionized form, and their hydrophobicity accounted for these differences. While carboxylic acids 4 and 5 were scarcely transformed in duckweed, 1-3 mainly underwent phase II conjugation with glucose for 1 and 2, malic acid for 3, glutamic acid for 2, and malonylglucose for 3, the chemical identities of which were confirmed by various spectrometric analyses (LC-MS, LC-MS/MS, and NMR) and/or HPLC cochromatography with reference synthetic standards.     

Anthocyanins in wild blueberries of Quebec: extraction and identification

Anthocyanins were extracted from a mixture of berries of Vaccinium angustifolium and Vaccinium myrtillo?des at 7.7 degrees C, 26 degrees C, and 79 degrees C using ethanol alone or ethanol acidified with hydrochloric, citric, tartaric, lactic, or phosphoric acids at a solvent to solid ratio of 10. The effect of these parameters on extracted anthocyanins stability was investigated. The pH-differential and HPLC-DAD methods were used to determine anthocyanin contents. Extracted anthocyanins were purified on a C-18 solid-phase extraction cartridge and characterized by HPLC/electrospray ionization/mass spectrometry (HPLC-ESI-MS/MS). Anthocyanins were identified according to their HPLC retention times, elution order, and MS fragmentation pattern and by comparison with standards and published data. Anthocyanin extractions gave different yields depending on the type of added acid and the extraction temperature. High yields of monomeric and total anthocyanins (26.3 and 28.9 mg/g of dry matter) were obtained at 79 degrees C using phosphoric acid. Extraction using tartaric acid at 79 degrees C provided the lowest degradation index (1.05). Anthocyanins were stable and browning by polyphenol oxidase was inhibited under these conditions. Of the six common anthocyanindins, five were identified in the extracts, namely, delpinidin, cyanidin, peonidin, petunidin, and malvidin; pelargonidin was not found. In addition to well-known major anthocyanins, new anthocyanins were identified for the first time in extracts of wild blueberries from Quebec.     

Solid-state bioconversion of phenolics from cranberry pomace and role of Lentinus edodes beta-glucosidase

Cranberry pomace contains large amounts of phenolic glycosides, which are important sources of free phenolics that have many food uses such as antioxidants, flavorings, and nutraceuticals. Our hypothesis was that these glycosides in cranberry pomace could be hydrolyzed by beta-glucosidase produced by Lentinus edodes during solid-state fermentation. On the basis of this hypothesis, our objective was to investigate the potential of using cranberry pomace as a substrate for the production of free phenolics and beta-glucosidase through solid-state fermentation by a food-grade fungus L. edodes. Our results suggested that L. edodes beta-glucosidase played a major role in release of phenolic aglycons from cranberry pomace during solid-state fermentation. After 50 days of cultivation, the yield of total free phenolics reached the maximum of 0.5 mg per g of pomace, while the beta-glucosidase activity was about 9 units per g of pomace. The enzyme exhibited optimal activity at 60 degrees C and at pH 3.5 and was stable at temperatures up to 50 degrees C and between pH 3 and 6.5. The major free phenolics produced from cranberry pomace were identified by HPLC as gallic acid, chlorogenic acid, p-hydroxybenzoic acid, and p-coumaric acid. These results suggest that cranberry pomace is a potential substrate for producing food-grade phenolics and fungal beta-glucosidase. The L. edodes beta-glucosidase showed good stability and tolerance to low pH and, therefore has potential applications in wine and juice processing for aroma and flavor enrichment through enzymatic hydrolysis of glucoside precursors.     

Phenolic profile of quince fruit (Cydonia oblonga Miller) (pulp and peel)

Qualitative and quantitative analyses of phenolic compounds were carried out on quince fruit samples from seven different geographical origins in Portugal. For each origin, both pulp and peel were analyzed by reversed-phase HPLC-DAD and HPLC-DAD/MS.The results revealed differences between the phenolic profiles of pulps and peels in all studied cases. The pulps contained mainly caffeoylquinic acids (3-, 4-, and 5-O-caffeoylquinic acids and 3,5-dicaffeoylquinic acid) and one quercetin glycoside, rutin (in low amount). The peels presented the same caffeoylquinic acids and several flavonol glycosides: quercetin 3-galactoside, kaempferol 3-glucoside, kaempferol 3-rutinoside, and several unidentified compounds (probably kaempferol glycoside and quercetin and kaempferol glycosides acylated with p-coumaric acid). The highest content of phenolics was found in peels.